: With a massive budget of 40 billion South Korean won , the series spared no expense on its battle scenes and historical sets.

Unlike typical "soft" historical romances, this drama is gritty, political, and heavily focused on military strategy. It depicts the power struggles within the royal court and the fierce resistance against the Tang Dynasty of China. It is a story of survival, patriotism, and the high cost of protecting a nation.

Traditional accounts often depict him as a ruthless leader who killed King Yeongnyu in 642 to install a puppet king, Bojang.